Mix improvement device for internal combustion engines

ABSTRACT

The device consists of a rotor (4) which is arranged in a suction pipe (1) and rotatably supported. The rotor (4) includes a hollow jacket body (5) on the outer wall of which vanes (2, 3) are arranged. A nozzle holder (26) is guided through the end (10) of the jacket body (5) directed against the air stream, which holder bears the injection nozzle (9) and is connected at the rear end with the fuel feed line (8). The fuel jets (24, 25) coming out of the injection nozzle (9) are directed against the inner wall (20) of the jacket body (5). This forms, at the same time, the jacket surface of the core hollow space (6) which widens toward the open end (11) of the jacket body (5). At the open end (11) is a centrifuge ring (14) with a spray edge (23). The rotor (4) is set in rotation by the stream of air flowing in the direction of the arrows (30, 31), and mixes the fuel centrifuged from the spray edge (23) homogeneously with the air. A measuring probe (28) determines the rpm of the rotor (4) and controls the influx of fuel through a pump to the fuel feed line (8) and thus to the injection nozzle (9).

TECHNICAL FIELD

The invention relates to a mix improvement device for internalcombustion engines with central injection, and with a flywheel arrangedin the suction pipe and set in rotation by the stream of suction air,which drives a rotor with an injection device for the fuel, and isconnected with the latter as well as a fuel feed line led into a hollowspace of the rotor.

BACKGROUND ART

In mix preparation and the measuring out of fuel for internal combustionengines, very high requirements are set for both a carburetor and aninjection unit as to the content of the exhaust in harmful substances.As we known, high proportions of harmful substances in the exhaust aretraced to an insufficient quality of mix, that is, mixing of fuel andcombustion air. To obtain a good quality of mix, an optimal mixing offuel and suction air, a homogeneous distribution of the fuel in thestream of air, and a homogeneous drop size are especially important.Especially in lean engine concepts where one works with a high excess ofair, these factors attain still greater importance.

Known means for attaining a good quality of mix are central injectionunits, such as those described in Kraftfahrttechnische Taschenbuch, 19thedition, VDI Verlag GmbH, Dusseldorf, on Pages 374 and 375. In thesedevices, an air mixing meter is installed between an air filter and amix former. In this air amount meter, there may be a damper, a heatingwire, or an ultrasonic measuring location. After flowing through the airamount meter, the suction air is led to the mix-forming point. Here, aninjection valve is arranged in the suction pipe to which fuel is fedunder pressure. The injection valve is equipped with a nozzle, and thefuel is injected through this latter into the suction air stream. In theflow direction of the suction air stream, below the injection valve, isa known choke valve for the regulation of the stream of air or mixture.The feeding of the fuel to the injection valve takes place through afuel pump. The delivery amount of this pump is determined by a control.The air amount meter serves as sensor for the control.

In addition to the injection valves, spiral scoops, supersonicvibrators, pulsating systems and other devices are sometimes used forimprovement of the quality of mix. Injection nozzles for pulsating orair-jacketed systems are technically elaborate in construction andproduction, and are relatively expensive. The injection valves andnozzles known today cannot assure an ideal thorough mixing of the fuelwith the air stream. Moreover, the droplet size of the injected fuel isdistributed over a wide spectrum, which in addition to poor mixformation, favors the danger of deposition of fuel on the parts of themix former. The known difficulties such as the increase of fuelconsumption and of harmful substances in the exhaust result from this.

From U.S. Pat. No. 4,044,081 is known a mix-improving device in which aninjection valve is combined with a rotary atomizer. A flywheel isarranged in the suction pipe of this device, and namely, before thechoke valve in the flow direction of the suction air stream. Theflywheel is connected with a rotor and drives the latter. The stream ofair flowing through the suction pipe sets the flywheel, and thus therotor, in rotation. An air line for hot air as well as a pressure linefor fuel are introduced into the rotor. In the zone where the two linesdischarge into the rotor, one or more eddy chambers are arranged insidein which an intensive mixing of the hot air with the injected fuelshould take place. In the peripheral zone of the eddy chamber, nozzlebores are arranged which make possible an outflow of the fuel-airmixture in the direction of the suction air stream. The outflow of thefuel-air mixture through the nozzle bores is promoted by the centrifugaleffect of the rotating rotor, while additional openings are alsoarranged in the suction pipe to obtain an improvement of the thoroughmixing of fuel and air. The arrangement of the additional miximprovement devices in the suction pipe makes it clear that even in thisdevice, the same difficulties occur as in the known injection valveswithout additional rotating mix improvers. The mix formation in the eddychamber and also the outflow through the nozzle channels are quitedifficult to control, and an ideal mix formation can hardly be obtained.The construction design of the device is expensive and hinders the flowof air in the suction pipe.

From German Disclosure No. 2,133,134 is known another carburetor forinternal combustion engines with a rotating atomizer. An atomizer pot isset in rotation mechanically from outside. In the center of theatomizing pot is an in-flow opening for fuel and an inset body with aregulating needle. Between the inner wall of the atomizer pot and theinset body is formed a ring-shaped suction channel from which the fuelis sucked into the stream of air. The measuring in of the fuel isdifficult here, and very inexact. The additional mechanical rotary driveis expensive and prone to disturbances. This device is intended for asuction carburetor and is not suitable for mixing devices with aninjection pump and an injection nozzle. The quality of mix is, inparticular, insufficient for the operation of lean engines.

SUMMARY OF THE INVENTION

It is the object of the invention to avoid the disadvantages of thestate of the art, and to provide a mix improvement device, and to assurean ideal mix formation with fine droplets and a homogeneous size ofdroplets. The device should have a simple structure and make possiblethe use of simple injection nozzles. In addition, the formation of mixshould be simplified for different conditions of operation, should makepossible the operation of the internal combustion engine as a leanengine, and a reduction of harmful substances in the exhaust should beobtained.

This object is solved according to the invention by the fact that therotor consists of a jacket body with a free core hollow space and acentrifuge ring which in the suction air stream closes directly againstthe end of the free core hollow space. The jacket surface of the freehollow core space diverges in the direction of flow of the suction airstream. The core hollow space of the jacket body is at least partlyclosed against the flow direction of the suction air stream. The fuelfeed line is introduced into the jacket body at the closed end of thecore hollow space and connected with an injection nozzle. This injectionnozzle is arranged in the zone of the lengthwise axis of the free corehollow space, and the spray jets are directed against the divergingjacket surfaces of the core hollow space.

The fuel injected through the injection nozzle into the core hollowspace is distributed because of the centrifugal effect of the rotatingjacket body over the jacket surface of the core hollow space. As aresult of the jacket surface diverging in the flow direction of thesuction air stream, the fuel film is driven in the direction of thewidened end of the core hollow space. The fuel film on the jacketsurface expands further and becomes ever thinner until at the widenedend of the core hollow space, it reaches the open end of the jacket bodyand with it the centrifuge ring. Here the fuel film flows on theperiphery of the centrifuge ring, tears away from the centrifuge ring bycentrifugal force, and is dissolved into very fine drops. The fuel dropscentrifuged out into the suction air stream are smaller than 10 micronsand are all of the same size. In this way, small fuel drops are mixedcompletely with the suction air and torn away with the latter, so thatthey cannot settle on the wall of the suction pipe. There results aquality of mix not obtained up to now. If the end of the jacket bodyagainst which the suction air stream flows is completely closed, thefuel film is advanced to the other end only as a result of the divergingjacket surface. The advancing movement can be additionally supported ifair entrance openings are arranged at the closed end of the jacket body.

In another embodiment of the device, the core hollow space is closed atthe widened end by a plate transverse to the axis of the rotor. Aring-shaped passage running parallel to the jacket surface of the corehollow space is arranged between this plate and the jacket body. Theturbulence of the air stream occurring in the suction pipe may affecteven the core hollow space in the jacket body. The plate arranged at thewidened end of the core hollow space prevents such disturbances, andfacilitates the forming of the fuel film on the jacket surface of thecore hollow space. The unhindered flow of the fuel film in the directionof the widened end of the core hollow space is made possible through thering-shaped passage.

A further improvement as to the forming of a uniform fuel film on thejacket surface of the core hollow space is obtained by the fact that, onthe inner wall of the jacket body and before the centrifuge ring, a ringchannel is arranged extending around the whole circumference of the corehollow space. This ring channel has a rectangular cross-section and iscut into the inner wall of the jacket body. In another preferredembodiment, the ring channel is formed by a local narrowing of the innerdiameter of the core hollow space. In the zone of this ring channel, athicker film of fluid is formed, and the narrowing of the core hollowspace which follows forms a higher flow resistance. Before the fuel filmcan overcome this resistance, it is completely distributed evenly overthe whole circumference of the ring channel, and only then flows on inthe direction of the widened end of the core hollow space.

For further dilution of the fluid film, and thus the reduction of thedrop size, the continuation of the core hollow space in the zone of thecentrifuge ring widens in a cone shape from inside outward. Theresultant conical jacket surface forms a ring-shaped spray edge in thezone of intersection with the outer surface of the centrifuge ring Theshape of this conical jacket surface allows, in a simple way, adaptingthe mix improvement device to the different shapes of the suction pipeand the stream of air. One preferred embodiment is distinguished by thefact that a ring-shaped cut-back is formed on the outer surface of thecentrifuge ring, and that this runs out into the ring-shaped spray edge.Through this cut-back, the fuel is prevented from running back oppositethe direction of the suction air stream along the outer surface of thecentrifuge ring. Otherwise, undesirable deposits of fuel might form onthe outer surface of the rotor, which would disturb the ideal forming ofa mix.

In other developments of the device, the outlet openings of theinjection nozzles are so designed that the fuel jets coming out strikeentirely against the jacket surface of the core hollow space. Thispermits operation with simple, cheap nozzles which can be used both inlow-pressure and high-pressure systems. Here, unlike the injectionvalves which inject the fuel directly into the stream of air, lowerrequirements need be set for the uniformity of fuel jets and drop size.The exact measurement of the drop size and the intensive mixing with thesuction air stream takes place only after the fluid film according tothe invention has been formed from the spray jets and centrifuged. Thedevice according to the invention allows supporting of the rotor on theclosed or on the open end of the jacket body, or even supporting bothends. In case of supporting at the upper end of the jacket body, thatis, at the end to which the air stream flows, no further parts after thespray edge on the centrifuge ring need be installed in the suction pipeIn this way, the danger of deposition of fuel on the construction partsis still further reduced.

In operation of the device in limit zones, the fuel drops centrifugedout may possibly deposit on the wall of the suction pipe It is well,therefore, to equip the rotor at the lower end with at least oneadditional rebound ring, and/or to arrange permanently at least onerebound ring in the suction pipe in the flow direction below the rotor.These rebound rings, even in single arrangement, effect an additionalatomization of the fuel drops striking, and prevent the deposit of fuelon the suction pipe. For certain designs of the device and rpm ranges,multiple arrangements of rebound rings provide ideal solutions.

In advantageous embodiments of the invention, the rpm of the flywheel isdirectly proportional to the amount of air sucked in. This is obtainedby the fact that the position and shape of the individual vanes areadapted, in a known way, to the shape of the suction pipe and the speedrange of the suction air stream. The linear dependence of the rpm of theflywheel on the amount of air makes possible a simple control of theforming of mix. This control is distinguished by the fact that thedevice has a measuring point for determining the rpm of the rotor. Thismeasuring point is connected through a control device with a fuel pump,and the control device forms with the fuel pump the regulating devicefor the amount of fuel. In further development, the control device isequipped additionally with sensors for the measurement of the densityand temperature of the suction air. The control used corresponds to theknown controls already in use for fuel injection systems. Unlike theknown devices, the device according to the invention requires noadditional metering of air amount since the amount of air can bedetermined from the rpm of the flywheel present. In addition to theregulating circuit described here, any known additional regulations maybe combined with the device and regulation according to the invention.Advantageously, the control device is set over the whole rpm range ofthe internal combustion engine to a constant ratio of air amount to fuelamount. The desired changing of the fuel-air mix ratio is obtained byfeeding additional air. For this purpose, inlet openings for additionalair are arranged on the suction pipe after the centrifuge ring in theflow direction of suction air stream. This additional air is takeneither from the fresh air filter or from the exhaust channel after theinternal combustion engine. The control of the additional amount of airalso takes place through the known control device. This control is muchsimpler than the changing necessary of the fuel pump delivery capacityin other known systems.

The advantages obtained through the invention are mainly to be seen inthe fact that a very homogeneous fuel-air mixture with extremely smallfuel drops is formed. This ideal mixing makes possible the operation ofinternal combustion engines with lambda values up to about 1.6. Fromthis results the advantage of a high utilization of fuel, and anextremely low content in pollutants of the exhaust because of the airexcess. The forming of a mix under different operating conditions isalso greatly simplified, and the whole mix-forming device has fewerparts and some simpler construction parts.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in detail below from embodiments withreference to the attached drawings.

FIG. 1 is a section through a mix-improvement device with a rotorsupported at the upper end of a jacket body;

FIG. 2 is a section through a mix-improvement device with a rotorsupported at the lower open end of a jacket body;

FIG. 3 is a section through the end of the jacket body and a centrifugering, in special design; and

FIG. 4 is a partial section from a suction pipe with a mix improvementdevice, a choke valve and feeding of additional air arranged after it.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 shows a section from a suction pipe 1 in the zone where the mixof suction air and fuel is formed. In the suction pipe is arranged arotor 4 which forms with vanes 2 and 3, a flywheel. The rotor 4 consistsfurther of a jacket body 5 which encloses a core hollow space 6. Thejacket body 5 is closed at one end 10 and open at the other end 11. Theclosed end 10 of the jacket body 5 is directed against the flowdirection of the suction air stream indicated by the arrow 30. Throughthe closed end 10 are introduced a fuel feed line 8 and a nozzle holdingdevice 26 into the zone of the core hollow space 6 of the rotor 4. Inthe zone of passage is arranged a slotted or labyrinth sealing ring 27.This arrangement prevents the suction air from being able to penetrateuncontrolled into the core hollow space 6. The nozzle holder 26 issupported and fixed into its position by radial stays 17, 18 against thesuction pipe. On the nozzle holder are arranged also bearings 15, 16 onwhich the jacket body 5 and the rotor 4 are braced and supported. At theend of the nozzle holder 26 is arranged an injection nozzle 9 which isconnected with the fuel feed line 8. This injection nozzle 9 is sodesigned that fuel jets 24, 25 are formed which arrive on the inner wall20 of the jacket body 5. This inner wall 20 is identical with the jacketsurface 20 of the core hollow space 6. The jacket surface 20 of the corehollow space 6 diverges into the flow direction 30, 31 of the suctionair stream, that is, the core hollow space 6 has a narrow end 12 and awidened end 13. The injection nozzle 9 is arranged in the zone of thenarrow part 12 of the core hollow space 6. The widened end 13 of thecore hollow space 6 forms a part of the open end 11 of the jacket body5. At the open end 11 of the jacket body 5 is arranged a centrifuge ring14 which is joined in one piece with the jacket body 5. In the zone ofthe centrifuge ring 14, the widened end 13 of core hollow space 6 isadditionally widened in cone shape from inside outward by which aconical jacket surface 21 is formed. This conical jacket surface 21intersects with the outer surface 22 of the centrifuge ring and forms aring-shaped spray edge 23. Before the centrifuge ring, a ring channel 19is cut in the inner wall of the jacket body 5 and extends around thewhole circumference of the core hollow space 6.

A measuring probe 28 is arranged on the suction pipe 1 in the zone ofthe vanes 2, 3 and is the means by which the rpm of the rotor 4 can bedetermined. The signals determined on the measuring probe 28 are fedthrough a line 29 to a control device, not shown. This is a knownelectronic control device such as that used in similar design, forexample, in the known Monojetronic units of the Bosch firm. This controldevice regulates, depending on the rpm of the rotor 4, the deliverycapacity of a fuel pump, also not shown, which delivers fuel through thefuel feed line 8 under pressure into the injection nozzle 9.

In the operation of the mix-forming device represented, there is a knownchoke valve after the rotor 4 in the suction pipe 1 in the flowdirection of the suction air stream. This is shown in FIG. 4 in theoperation of the internal combustion arranged after it. A vacuum resultsin the suction pipe 1 whereby, with the choke valve opened, a suctionair stream results in the direction of the arrows 30, 31. This suctionair stream flows through the flywheel with vanes 2, 3 and sets it inrotation. The setting angle and shape of the vanes 2, 3 are so chosenthat the rpm of the rotor 4 and the amount of suction air are directlyproportional or linear. At the same time through the injection nozzle 9,fuel is sprayed against the inner wall 20 of the jacket body 5. Therotor 4 rotates according to the amount of air with an rpm of up to100,000 revolutions per minute. Through this rapid rotation, the fuel isevenly distributed along the circumference of the inner wall 20 andforms a uniform fuel film. This fuel film flows from the narrow end 12of the core hollow space 6 toward the widened end 13. This flow iseffected by the diverging jacket surface or inner wall 20 and therotation of the jacket body 5. In the zone of the ring channel 19, thefuel accumulates until the latter is filled. After this, the fuel filmis formed again thin and uniform, and reaches the zone of the conicaljacket surface 21. Through this conical widening in the zone of thecentrifuge ring 14, the fuel film is additionally thinned, so that itdissolves into drops of less than 10 microns on reaching the spray edge23. The centrifuged fuel drops are all of practically the same size, andare mixed intensively with the suction air stream, and the fuel-airmixture formed flows in the direction of the arrow 31 toward theinternal combustion engine. In this arrangement, the amount of fuelinjected at the injection nozzle 9 is regulated dependent on the rpm ofthe rotor 4 and the position of the choke valve, by means of the controldevice and the fuel pump. To refine the regulation besides the probe 28for rpm measurement, still other probes, for example, for measurement ofdensity and temperature of the suction air may be connected in the knownway with the control device. The regulation zone of this mix-formingdevice extends over a range of Lambda values from 0.9 to 1.6.

FIG. 2 shows essentially the same mix improvement or mixing device asFIG. 1. Here, in variance from FIG. 1, the rotor 4 is supported at theopen end 11 of the jacket body 5. For this purpose, a plate 32 providedwith a bearing pin 34 is arranged at the widened end 13 of the corehollow space 6. On the bearing pin 34 are arranged two bearings 15, 16which, in turn are supported on the bearing 36. Stays 37, 38 join thebearing 36 with the suction pipe 1 and hold the rotor 4 in the desiredposition.

A ring-shaped passage 33 running parallel to the jacket surface 20 isarranged between the plate 32 and the inner wall or jacket surface 20 ofthe jacket body 5. The jacket body 5 is supported by means of severalstays against the plate 32. The plate 32 has for its purpose theprotection of the core hollow space 6 against disturbances by thesuction air stream, for example, the formation of eddies below therotor. In this design, one or more air channels 35 are arranged in thezone of the passage of the nozzle holder 26 through the closed end 10 ofthe jacket body 5, which make possible the entrance of the suction airinto the core hollow space 6. The air flowing through the channels 35into the core hollow space 6 supports the fuel flow along the inner wall20 and additionally damps the disturbances already mentioned, forexample, eddy formation. The solution represented in FIG. 2 permits asimple installation and removal of the injection nozzle 9 without havingto remove the rotor 4 also. Otherwise, this embodiment has the sameadvantages and properties, and the mix forming takes place in the sameway.

For further improvement of mix formation in the zone of the lower end ofthe rotor 4, an additional rebound ring 60 is arranged. This reboundring 60 is connected solidly through stays 61 with the open end 11 ofthe jacket body 5 and rotates with the latter. Here, the rebound ring 60is so arranged that the drops centrifuged out by the spray edge 23strike against the inner surface of the rebound ring 60. The dropsstriking at very high speed are additionally atomized and carried alongby the stream of air.

In the starting of the device or in other not completely controlled rpmranges of the rotor 4, the mix may deposit on the wall of the suctionpipe 1 and form there an undesirable film or larger drops. To preventthe drops from the rotating parts from being centrifuged onto the wallof the suction pipe 1, a stationary rebound ring 62 is installed. Thisis joined through the stays 63 with the suction pipe 1. The drops offuel are centrifuged by the rebound ring 60, or if the latter is notinstalled, by the spray edge 23 against the inner surface of the reboundring 62. If a fuel film or larger drops are formed under limitconditions on this inner surface, these flow to the edge 64 and arethere torn away by the stream of air and atomized. In this way, theforming of fuel deposits on the suction pipe 1 is prevented, and a goodforming of mix is assured even in border zones. The rebound rings 60, 62may be arranged in the device shown, in common or only one in each case.

FIG. 3 shows a special design of the centrifuge ring 14 in which theflowing back of fuel along the outer wall 40 of the jacket body 6 isprevented. For this, on the outer surface of the centrifuge ring 14 isarranged a cut-back 41 which runs out into the ring-shaped spray edge23. Here also, the core hollow space 6 is conically widened in the zoneof the centrifuge ring 14 from inside outward, and forms a conicaljacket surface 21. The arrangement of the cut-back 41 and the sharpspray edge 23 prevents, in each case, a flowing back of fuel, andpromotes the tearing away of the fuel film at the edge 23 by the streamof air in the form of very fine drops. In FIG. 3 is shown anotherpossibility for the design of a ring channel 42. The inner diameter ofthe core hollow space 6 is narrowed locally, forming a narrow part 43.In this way, there results after it a pocket-shaped ring channel 42 inwhich a thicker fuel film is formed than in the other zones of the innerwall 20. This thicker fuel film makes possible, on the one hand, anequalizing of the film over the whole circumference of the inner wall20, and a more uniform flowing out of the fuel film in the direction ofthe spray edge 23.

The representation in FIG. 4 shows a complete mix-forming device insimplified design. In the suction pipe 1 is arranged the rotor 4 withthe jacket body 5 and the vanes 2, 3. The feeding of fuel into the corehollow space 6 of the jacket body 5 takes place through the injectionnozzle 9, the nozzle holder 26, and the fuel feed line 8. The rotor 4 issupported by means of the bearing pin 34 through bearings 15, 16 in thebearing 36. After the rotor in the flow direction of the suction air,there is a choke valve 45 which is connected with a setting device 46.In the flow direction, again below the choke valve an inlet opening 47in the form of a ring gap is arranged in the suction pipe 1 and issurrounded by a ring-shaped air channel 48. This ring gap 47 forms aninlet opening for additional air which can be suction ed from the ringchannel 48 into the suction pipe 1. The ring channel 48 is connectedwith an air feed line 49 which brings additional air from the fresh airfilter or hot exhaust from the exhaust channel to the ring channel 48.In this air feed line 49, there is also a choke valve 50 which isconnected with a setting device 51, 52.

Connection lines 54, 55 and 29 lead from an electronic control device tothe corresponding setting devices or sensors. The line 29 connects thecontrol device 53 with the sensor 28 for the measuring of the rpm of therotor 4. The connection line 54 controls the fuel pump and containsother in and out lines for additional control and measuring members. Theconnection line 55 serves for the switching of the setting members 51,52 or the choke valve 50 into the air feed line 49.

In the mix-forming device shown in FIG. 4, the injection nozzle 9 isalways fed enough fuel so that a mixture is formed with a Lambda number0.9, that is, a rich mixture. This ratio is kept constant over the wholerange of air amount variation or change of rpm of the rotor 4. Becauseof the high quality of mix which results after the spray edge 23, themix must not be more strongly enriched, even in extreme situations. Innormal operation, additional air is mixed with the mix stream after therotor 4 through the ring gap 47, in which case ordinary engines may beoperated with a Lambda number of about 1.25. This is contrary to thecarburetors or injection units known up to now, in which a Lambda numberof about 1.05 must be set. In this way, much less carbon monoxide,hydrocarbons and nitrous oxide results in the exhaust. The deviceaccording to FIG. 4 is so equipped that enough additional air can be fedthat a Lambda number of up to about 1.6 can be reached, with whichspecial so-called lean engines can be operated. Thanks to thehomogeneous thorough mixing of the suction air and fuel as well as thesmall size of fuel drops, even with this high admixture of additionalair, there is no deposition of fuel on the walls of the suction pipe.

This invention has been described with reference to preferredembodiments. Modifications and changes may become apparent to oneskilled in the art upon reading and understanding this specification. Itis intended to cover all such modifications and changes within the scopeof the appended claims.

Having described embodiments of the invention, I claim:
 1. Mix-improving device for internal combustion engines with central injection, and with a flywheel arranged in a suction pipe and set in rotation by the suction air stream, which drives a rotor with an injection device for the fuel, and is connected with the latter and a fuel feed line guided in a hollow space of the rotor, with the distinction that the rotor (4) consists of a jacket body (5) with a free core hollow space (6) and a centrifuge ring (14) which, in the flow direction of the stream of suction air, adjoins directly the end (11) of the free core hollow space (6), the jacket surface (20) diverges in the flow direction (30) of the stream of suction air, the core hollow space (6) of the jacket body (5) is at least partly closed opposite the flow direction (30) of the stream of suction air, the fuel feed line (8) is introduced at the closed end (10) of the core hollow space (6) and is connected with an injection nozzle (9), the injection nozzle (9) is arranged in the zone of the longitudinal axis (7) of the free core hollow space (6), and the spray jets (24, 25) are directed against the diverging jacket surface (20) of the core hollow space (6).
 2. Mix-improving device according to claim 1, with the distinction that the core hollow space (6) is closed at the widened end (13) by a plate (32) standing transverse to the rotor axis (7), and a ring-shaped passage (33) running parallel to the jacket surface (20) of the core hollow space (6) is arranged between the plate (32) and the jacket body (5).
 3. Mix-improving device according to claim 1 with the distinction that a ring channel (19) extending over the whole circumference of the core hollow space (6) is arranged against the inner wall (20) of the jacket body (5) and before the centrifuge ring (14).
 4. Mix-improving device according to claim 3, with the distinction that the ring channel (19) has a rectangular cross-section, and is cut into the inner wall (20) of the jacket body (5).
 5. Mix-improving device according to claim 3, with the distinction that the ring channel (19) is formed by a local narrowing (43) of the inner diameter of the core hollow space (6).
 6. Mix-improving device according to claim 1 with the distinction that the continuation of the core hollow space (6) is widened in a cone shape in the zone of the centrifuge ring (14) from inside outward, and the resultant conical jacket surface (21) in the zone of intersection with the outer surface (22) of the centrifuge ring (14) forms a ring-shaped spray edge (23).
 7. Mix-improving device according to claim 1 with the distinction that a ring-shaped cut back (41) is formed against the outer surface (22) of the centrifuge ring (14) and runs out into the ring-shaped spray edge (23).
 8. Mix-improving device according to claim 1 with the distinction that the outlet openings of the injection nozzle (9) are so designed that the fuel jets (24, 25) coming out strike entirely against the jacket surface (20) of the core hollow space (6) in the rotor (4).
 9. Mix-improving device according to claim 1 with the distinction that the rotor (4) is supported on the upper end (10), at least partly closed, of the jacket body (5), and the bearings (15, 16) are supported against the fuel feed line (8) and/or the injection nozzle (9, 26).
 10. Mix-improving device according to claim 1 with the distinction that the rotor (4) is supported at the open end (11) of the jacket body (5) and after the centrifuge ring (14), and the bearing (36) is supported through radial stays (37, 38) against the suction pipe (1).
 11. Mix-improving device according to claim 1 with the distinction that the rotor (4) is supported in the flow direction (30) of the suction air stream before the injection nozzle (9) and after the centrifuge ring (14).
 12. Mix-improving device according to claim 1 with the distinction that the rotor (4), at the lower end, is equipped with at least one additional rebound ring (60).
 13. Mix-improving device according to claim 1 with the distinction that at least one rebound ring (62) is permanently arranged in the suction pipe 1 below the rotor (4) in the flow direction.
 14. Mix-improving device according to claim 1 with the distinction that the rpm of the flywheel with vanes (2, 3) is directly proportional to the amount of air suctioned.
 15. Mix-improving device according to claim 1 with the distinction that the device has a measuring probe (28) for the measurement of the rpm of the rotor (4), the measuring probe (28) is connected through a control device (53) with a fuel pump, and the control device (53) forms with the fuel pump the regulating device for the amount of fuel.
 16. Mix-improving device according to claim 15, with the distinction that the control device (53) is additionally equipped with sensors for measurement of the density and the temperature of the suction air.
 17. Mix-improving device according to claim 15, with the distinction that the control device (53) is set to a constant ratio of air amount to fuel amount over the whole rpm range of the internal combustion engine.
 18. Mix-improving device according to claim 1 with the distinction that inlet openings (47) for additional air are arranged in the suction pipe (1) after the centrifuge ring (14) in the flow direction (30) of the suction air stream.
 19. Mix-improving device according to claim 18, with the distinction that the inlet openings (47) for the additional air are connected through an air channel (48, 49) with the fresh air filter.
 20. Mix-improving device according to claim 18, with the distinction that the inlet openings (47) for the additional air are connected through an air channel (48, 49) with the exhaust channel after the internal combustion engine. 